Ambien is called Maisuri (マイスリ) here Richard, my doctor doesn't seem shy in handing them out. In fact I've had no problem being prescribed even Rohypnol here.
I must echo the warnings of others here, test them out at home first. I find it easy to resisit the urge to sleep with Ambien and by doing that you can gain (or I can at least) considerable "recreational effects" accompanied by a certain degree of amnsesia in the morning. Ymmv. Just be aware.